# Variable Sized Arrays

### Problem Statement :

```Consider an n - element array, a, where each index i in the array a contains a reference to an array of  Ki integers (where the value Ki of varies from array to array). See the Explanation section below for a diagram.

Given a , you must answer q queries. Each query is in the format i j, where i denotes an index in array  a and j denotes an index in the array located at a[i] . For each query, find and print the value of element  j in the array at location a[i] on a new line.

Input Format

The first line contains two space-separated integers denoting the respective values of n (the number of variable-length arrays) and q (the number of queries).

Each line i of n the subsequent lines contains a space-separated sequence in the format k a[i]0 a[i]1 … a[i]k-1 describing the k-element array located at a[i].

Each of the q subsequent lines contains two space-separated integers describing the respective values of i (an index in array ) and j (an index in the array referenced by a[i] ) for a query.

Constraints

1 <= n <= 10^5
1 <= q <= 10^5
1 <= k  <= 3 * 10^5
0 <= i  < n
0 <= j  < k

All indices in this challenge are zero-based.
All the given numbers are non negative and are not greater than  10^6.

Output Format

For each pair of i and j values (i.e., for each query), print a single integer that denotes the element located at index j of the array referenced by a[ i ]. There should be a total of q lines of output.```

### Solution :

```                            ```Solution in C :

int n, q; cin >> n >> q;
int **v = new int*[n];
for(int j=0;j<n;j++){
int k; cin >> k;
v[j] = new int[k];
for(int i=0;i<k;i++){
int x; cin >> x;
v[j][i] = x;
}
}
for(int i=0;i<q;i++){
int a, b; cin >> a >> b;
cout << v[a][b]<<endl;
}
return 0;
}```
```

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